This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. As important elements of human cytokinesis are highly conserved in S. cerevisiae, I am exploiting yeast's experimental advantages to study cytokinesis. To isolate cytokinetic ring contraction from related processes of the cell and give greater control of experimental parameters, I am developing a cell free functional assay for cytokinetic ring contraction. Excitingly, I have found it possible to isolate intact cytokinetic apparatus from yeast. To move to a definitive list of machinery sufficient for cytokinetic ring contraction, I am seeking to identify novel factors that are associated with partially purified, intact cerevisiae cytokinesis apparatus.